The Perseus Cluster of Galaxies

2008-05-20 Jean-Charles Cuillandre

Here is one of the largest objects that anyone will ever see on the sky. Each of these fuzzy blobs is a galaxy, together making up the Perseus Cluster, one of the closest clusters of galaxies. The cluster is seen through a foreground of faint ...

Flying Over the Columbia Hills of Mars

2008-05-19

What it would be like to fly over Mars? Combining terrain data from the orbiting Mars Reconnaissance Orbiter spacecraft with information about the robotic Spirit rover currently rolling across Mars has resulted in a digital movie that shows what ...

On the Origin of Gold

2008-05-18

Where did the gold in your jewelry originate? No one is completely sure. The relative average abundance in our Solar System appears higher than can be made in the early universe, in stars, and even in typical supernova explosions. Some ...

Logarithmic Spirals

2008-05-17

Uncomfortably close Typhoon Rammasun (right) and 25 million light-year distant galaxy M101 don't seem to have much in common. For starters, Rammasun was only a thousand kilometers or so across while M101 (aka the Pinwheel Galaxy) spans about ...

Circles in the Sky

2008-05-16 Jean-Marc Lecleire

Gazing skyward on a sunny day in May, photographer Jean-Marc Lecleire captured this engaging display of ice halos forming complete circles in the sky. Recorded with a fish-eye lens from a spot near the grand Château de Chambord in France, the ...

Sideways Galaxy NGC 3628

2008-05-15 Keith Quattrocchi

Dark dust lanes cut across the middle of this gorgeous island universe, a strong hint that NGC 3628 is a spiral galaxy seen sideways. About 35 million light-years away in the northern springtime constellation Leo, NGC 3628 also bears the ...

A Supply Ship Docks with the...

2008-05-14

Looking out a window of the International Space Station brings breathtaking views. Visible vistas include a vast and colorful Earth, a deep dark sky, and an occasional spaceship sent to visit the station. Visible early last month was a Soyuz ...

Ancient Craters of Southern Rhea

2008-05-13

Saturn's ragged moon Rhea has one of the oldest surfaces known. Estimated as changing little in the past billion years, Rhea shows craters so old they no longer appear round – their edges have become compromised by more recent cratering. Like ...

The M81 Galaxy Group Through the...

2008-05-12 Jordi Gallego

Large galaxies and faint nebulae highlight this deep image of the M81 Group of galaxies. First and foremost in the wide-angle 12-hour exposure is the grand design spiral galaxy M81, the largest galaxy visible in the image. M81 is ...

Retrograde Mars

2008-05-11 Tunç Tezel

Why would Mars appear to move backwards? Most of the time, the apparent motion of Mars in Earth's sky is in one direction, slow but steady in front of the far distant stars. About every two years, however, the Earth passes Mars as they orbit ...